docs(agents): E2B/Daytona sandboxes, fleshed-out examples, design patterns first

[eersnington]

Polishes the Agents docs (agents/ only).

Sandboxes

• Examples use E2B, with Daytona as an alternative. The agentOS provider ships later, so it's no longer mentioned.
• The Quickstart shows e2b.ts and daytona.ts side by side.

Structure

• Core order: Design Patterns, LLM API Keys, Sandboxes, Custom Tools, Session Lifecycle. "Next" links follow it, and the Quickstart and Pi pages point to Design Patterns.
• The Overview has Quickstart and Pi cards at the top and a Concepts section. Pi is badged Beta.

Examples

• Each design pattern is a complete server and client example. Patterns are keyed per user, Slack thread, or GitHub issue, and subagents are support specialists with their own tools.
• Concept pages gain client files.
• The models are mixed: Opus 5.5 by default, with Haiku, Sonnet, and GPT-5.x for narrow jobs.
• Prompts work in an empty sandbox.
• Connectors queue mentions so none are dropped mid-run.
• Fixes: PR checkout, the apiKeys empty-string fallback, the reviewer's missing repo, and the auth placeholder comment.

Writing

• Removed bloat.
• No sentences start with code.
• Diagrams redrawn: sandboxes, human in the loop, custom tools, and keys.

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[the-company-company]

🟠 1 medium · 🔵 2 low

_{Reviewed commit d6dcb28.}

[the-company-company]

🟠 Medium · Failed replies are permanently discarded

Any failure from prompt, getLastAssistantText, or postReply is caught, after which finally removes the comment from durable state and the action returns successfully. A transient model/provider/GitHub failure therefore produces no reply and can never be retried. The same drain implementation appears in the Discord, Linear, and Slack examples. Only dequeue after postReply succeeds; on failure, retain the head item and rethrow or schedule an explicit bounded retry/backoff.

[the-company-company]

🔵 Low · Multi-file examples bypass the workspace contract

This new group spans related server.ts and client.ts modules but omits workspace, contrary to the repository's required multi-file-example convention. The other groups added on this page, plus the new/expanded groups in agent-to-agent, quickstart, schedules, subagents, user-subscriptions, and workflows, do the same. Mark these as <CodeGroup workspace> so the files are treated and checked as one compilable example.

[the-company-company]

🔵 Low · Local portal state is committed as documentation

This generated editor/runtime metadata hard-codes one developer's /home/user/workspace/repos/website checkout and transient port 31227; it is not portable project configuration and sits inside the published docs source tree. Remove both .amp/portals files and ignore this local state so another portal run cannot reintroduce it.